usr/src/cmd/cmd-inet/usr.sbin/snoop/snoop_ipaddr.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <ctype.h>
  29 #include <sys/types.h>
  30 #include <sys/socket.h>
  31 #include <sys/sockio.h>
  32 #include <net/if.h>
  33 #include <netinet/in_systm.h>
  34 #include <netinet/in.h>
  35 #include <netinet/if_ether.h>
  36 #include <netinet/ip.h>
  37 #include <netdb.h>
  38 #include <string.h>
  39 #include <signal.h>
  40 #include <setjmp.h>
  41 #include <arpa/inet.h>
  42 #include "snoop.h"
  43
  44 static sigjmp_buf nisjmp;
  45
  46 #define MAXHASH 1024  /* must be a power of 2 */
  47
  48 #define SEPARATORS " \t\n"
  49
  50 struct hostdata {
  51         struct hostdata *h_next;
  52         char            *h_hostname;
  53         int             h_pktsout;
  54         int             h_pktsin;
  55 };
  56
  57 struct hostdata4 {
  58         struct hostdata4        *h4_next;
  59         char            *h4_hostname;
  60         int             h4_pktsout;
  61         int             h4_pktsin;
  62         struct in_addr  h4_addr;
  63 };
  64
  65 struct hostdata6 {
  66         struct hostdata6        *h6_next;
  67         char            *h6_hostname;
  68         int             h6_pktsout;
  69         int             h6_pktsin;
  70         struct in6_addr h6_addr;
  71 };
  72
  73 static struct hostdata *addhost(int, const void *, const char *, char **);
  74
  75 static struct hostdata4 *h_table4[MAXHASH];
  76 static struct hostdata6 *h_table6[MAXHASH];
  77
  78 #define iphash(e)  ((e) & (MAXHASH-1))
  79
  80 /* ARGSUSED */
  81 static void
  82 wakeup(int n)
  83 {
  84         siglongjmp(nisjmp, 1);
  85 }
  86
  87 extern char *inet_ntoa();
  88
  89 static struct hostdata *
  90 iplookup(struct in_addr ipaddr)
  91 {
  92         register struct hostdata4 *h;
  93         struct hostent *hp = NULL;
  94         struct netent *np;
  95         int error_num;
  96         struct hostdata *retval;
  97
  98         for (h = h_table4[iphash(ipaddr.s_addr)]; h; h = h->h4_next) {
  99                 if (h->h4_addr.s_addr == ipaddr.s_addr)
 100                         return ((struct hostdata *)h);
 101         }
 102
 103         /* not found.  Put it in */
 104
 105         if (ipaddr.s_addr == htonl(INADDR_BROADCAST))
 106                 return (addhost(AF_INET, &ipaddr, "BROADCAST", NULL));
 107         if (ipaddr.s_addr == htonl(INADDR_ANY))
 108                 return (addhost(AF_INET, &ipaddr, "OLD-BROADCAST", NULL));
 109
 110         /*
 111          * Set an alarm here so we don't get held up by
 112          * an unresponsive name server.
 113          * Give it 3 sec to do its work.
 114          */
 115         if (! rflg && sigsetjmp(nisjmp, 1) == 0) {
 116                 (void) snoop_alarm(3, wakeup);
 117                 hp = getipnodebyaddr((char *)&ipaddr, sizeof (int),
 118                     AF_INET, &error_num);
 119                 if (hp == NULL && inet_lnaof(ipaddr) == 0) {
 120                         np = getnetbyaddr(inet_netof(ipaddr), AF_INET);
 121                         if (np)
 122                                 return (addhost(AF_INET, &ipaddr, np->n_name,
 123                                     np->n_aliases));
 124                 }
 125                 (void) snoop_alarm(0, wakeup);
 126         }
 127
 128         retval = addhost(AF_INET, &ipaddr,
 129             hp ? hp->h_name : inet_ntoa(ipaddr),
 130             hp ? hp->h_aliases : NULL);
 131         if (hp != NULL)
 132                 freehostent(hp);
 133         return (retval);
 134 }
 135
 136 static struct hostdata *
 137 ip6lookup(const struct in6_addr *ip6addr)
 138 {
 139         struct hostdata6 *h;
 140         struct hostent *hp = NULL;
 141         int error_num;
 142         char addrstr[INET6_ADDRSTRLEN];
 143         char *addname;
 144         struct hostdata *retval;
 145
 146         for (h = h_table6[iphash(((uint32_t *)ip6addr)[3])]; h;
 147             h = h->h6_next) {
 148                 if (IN6_ARE_ADDR_EQUAL(&h->h6_addr, ip6addr))
 149                         return ((struct hostdata *)h);
 150         }
 151
 152         /* not in the hash table, put it in */
 153         if (IN6_IS_ADDR_UNSPECIFIED(ip6addr))
 154                 return (addhost(AF_INET6, ip6addr, "UNSPECIFIED", NULL));
 155
 156         /*
 157          * Set an alarm here so we don't get held up by
 158          * an unresponsive name server.
 159          * Give it 3 sec to do its work.
 160          */
 161         if (! rflg && sigsetjmp(nisjmp, 1) == 0) {
 162                 (void) snoop_alarm(3, wakeup);
 163                 hp = getipnodebyaddr(ip6addr, sizeof (struct in6_addr),
 164                     AF_INET6, &error_num);
 165                 (void) snoop_alarm(0, wakeup);
 166         } else {
 167                 hp = NULL;
 168         }
 169
 170         if (hp != NULL)
 171                 addname = hp->h_name;
 172         else {
 173                 (void) inet_ntop(AF_INET6, ip6addr, addrstr, INET6_ADDRSTRLEN);
 174                 addname = addrstr;
 175         }
 176
 177         retval = addhost(AF_INET6, ip6addr, addname, hp ? hp->h_aliases : NULL);
 178         if (hp != NULL)
 179                 freehostent(hp);
 180         return (retval);
 181 }
 182
 183 static struct hostdata *
 184 addhost(int family, const void *ipaddr, const char *name, char **aliases)
 185 {
 186         struct hostdata **hp, *n = NULL;
 187         extern FILE *namefile;
 188         int hashval;
 189         static char aname[128];
 190         char *np;
 191         static struct hostdata h;
 192         int ind;
 193
 194         switch (family) {
 195         case AF_INET:
 196                 n = (struct hostdata *)malloc(sizeof (struct hostdata4));
 197                 if (n == NULL)
 198                         goto alloc_failed;
 199
 200                 memset(n, 0, sizeof (struct hostdata4));
 201                 n->h_hostname = strdup(name);
 202                 if (n->h_hostname == NULL)
 203                         goto alloc_failed;
 204
 205                 ((struct hostdata4 *)n)->h4_addr =
 206                     *(const struct in_addr *)ipaddr;
 207                 hashval = ((struct in_addr *)ipaddr)->s_addr;
 208                 hp = (struct hostdata **)&h_table4[iphash(hashval)];
 209                 break;
 210         case AF_INET6:
 211                 n = (struct hostdata *)malloc(sizeof (struct hostdata6));
 212                 if (n == NULL)
 213                         goto alloc_failed;
 214
 215                 memset(n, 0, sizeof (struct hostdata6));
 216                 n->h_hostname = strdup(name);
 217                 if (n->h_hostname == NULL)
 218                         goto alloc_failed;
 219
 220                 memcpy(&((struct hostdata6 *)n)->h6_addr, ipaddr,
 221                     sizeof (struct in6_addr));
 222                 hashval = ((const int *)ipaddr)[3];
 223                 hp = (struct hostdata **)&h_table6[iphash(hashval)];
 224                 break;
 225         default:
 226                 fprintf(stderr, "snoop: ERROR: Unknown address family: %d",
 227                     family);
 228                 exit(1);
 229         }
 230
 231         n->h_next = *hp;
 232         *hp = n;
 233
 234         if (namefile != NULL) {
 235                 if (family == AF_INET) {
 236                         np = inet_ntoa(*(const struct in_addr *)ipaddr);
 237                         if (np) {
 238                                 (void) fprintf(namefile, "%s\t%s", np, name);
 239                                 if (aliases) {
 240                                         for (ind = 0;
 241                                             aliases[ind] != NULL;
 242                                             ind++) {
 243                                                 (void) fprintf(namefile, " %s",
 244                                                     aliases[ind]);
 245                                         }
 246                                 }
 247                                 (void) fprintf(namefile, "\n");
 248                         }
 249                 } else if (family == AF_INET6) {
 250                         np = (char *)inet_ntop(AF_INET6, (void *)ipaddr, aname,
 251                             sizeof (aname));
 252                         if (np) {
 253                                 (void) fprintf(namefile, "%s\t%s", np, name);
 254                                 if (aliases) {
 255                                         for (ind = 0;
 256                                             aliases[ind] != NULL;
 257                                             ind++) {
 258                                                 (void) fprintf(namefile, " %s",
 259                                                     aliases[ind]);
 260                                         }
 261                                 }
 262                                 (void) fprintf(namefile, "\n");
 263                         }
 264                 } else {
 265                         (void) fprintf(stderr, "addhost: unknown family %d\n",
 266                             family);
 267                 }
 268         }
 269         return (n);
 270
 271 alloc_failed:
 272         if (n)
 273                 free(n);
 274         (void) fprintf(stderr, "addhost: no mem\n");
 275
 276         aname[0] = '\0';
 277         memset(&h, 0, sizeof (struct hostdata));
 278         h.h_hostname = aname;
 279         return (&h);
 280 }
 281
 282 char *
 283 addrtoname(int family, const void *ipaddr)
 284 {
 285         switch (family) {
 286         case AF_INET:
 287                 return (iplookup(*(const struct in_addr *)ipaddr)->h_hostname);
 288         case AF_INET6:
 289                 return (ip6lookup((const struct in6_addr *)ipaddr)->h_hostname);
 290         }
 291         (void) fprintf(stderr, "snoop: ERROR: unknown address family: %d\n",
 292             family);
 293         exit(1);
 294         /* NOTREACHED */
 295 }
 296
 297 void
 298 load_names(fname)
 299         char *fname;
 300 {
 301         char buf[1024];
 302         char *addr, *name, *alias;
 303         FILE *f;
 304         unsigned int addrv4;
 305         struct in6_addr addrv6;
 306         int family;
 307         void *naddr;
 308
 309         (void) fprintf(stderr, "Loading name file %s\n", fname);
 310         f = fopen(fname, "r");
 311         if (f == NULL) {
 312                 perror(fname);
 313                 return;
 314         }
 315
 316         while (fgets(buf, 1024, f) != NULL) {
 317                 addr = strtok(buf, SEPARATORS);
 318                 if (addr == NULL || *addr == '#')
 319                         continue;
 320                 if (inet_pton(AF_INET6, addr, (void *)&addrv6) == 1) {
 321                         family = AF_INET6;
 322                         naddr = (void *)&addrv6;
 323                 } else if ((addrv4 = inet_addr(addr)) != (ulong_t)-1) {
 324                         family = AF_INET;
 325                         naddr = (void *)&addrv4;
 326                 }
 327                 name = strtok(NULL, SEPARATORS);
 328                 if (name == NULL)
 329                         continue;
 330                 while ((alias = strtok(NULL, SEPARATORS)) != NULL &&
 331                     (*alias != '#')) {
 332                         (void) addhost(family, naddr, alias, NULL);
 333                 }
 334                 (void) addhost(family, naddr, name, NULL);
 335                 /* Note: certain addresses such as broadcast are skipped */
 336         }
 337
 338         (void) fclose(f);
 339 }
 340
 341 /*
 342  * lgetipnodebyname: looks up hostname in cached address data. This allows
 343  * filtering on hostnames from the .names file to work properly, and
 344  * avoids name clashes between domains. Note that only the first of the
 345  * ipv4, ipv6, or v4mapped address will be returned, because the
 346  * cache does not contain information on multi-homed hosts.
 347  */
 348 /*ARGSUSED*/
 349 struct hostent *
 350 lgetipnodebyname(const char *name, int af, int flags, int *error_num)
 351 {
 352         int i;
 353         struct hostdata4 *h;
 354         struct hostdata6 *h6;
 355         static struct hostent he;               /* host entry */
 356         static struct in6_addr h46_addr[MAXADDRS];      /* v4mapped address */
 357         static char h_name[MAXHOSTNAMELEN];     /* hostname */
 358         static char *list[MAXADDRS];            /* addr_list array */
 359         struct hostent *hp = &he;
 360         int ind;
 361
 362         (void) memset((char *)hp, 0, sizeof (struct hostent));
 363         hp->h_name = h_name;
 364         h_name[0] = '\0';
 365         strcpy(h_name, name);
 366
 367         hp->h_addrtype = AF_INET6;
 368
 369         hp->h_addr_list = list;
 370         for (i = 0; i < MAXADDRS; i++)
 371                 hp->h_addr_list[i] = NULL;
 372         ind = 0;
 373
 374         /* ipv6 lookup */
 375         if (af == AF_INET6) {
 376                 hp->h_length = sizeof (struct in6_addr);
 377                 for (i = 0; i < MAXHASH; i++) {
 378                         for (h6 = h_table6[i]; h6; h6 = h6->h6_next) {
 379                                 if (strcmp(name, h6->h6_hostname) == 0) {
 380                                         if (ind >= MAXADDRS - 1) {
 381                                                 /* too many addresses */
 382                                                 return (hp);
 383                                         }
 384                                         /* found ipv6 addr */
 385                                         hp->h_addr_list[ind] =
 386                                             (char *)&h6->h6_addr;
 387                                         ind++;
 388                                 }
 389                         }
 390                 }
 391         }
 392         /* ipv4 or v4mapped lookup */
 393         if (af == AF_INET || (flags & AI_ALL)) {
 394                 for (i = 0; i < MAXHASH; i++) {
 395                         for (h = h_table4[i]; h; h = h->h4_next) {
 396                                 if (strcmp(name, h->h4_hostname) == 0) {
 397                                         if (ind >= MAXADDRS - 1) {
 398                                                 /* too many addresses */
 399                                                 return (hp);
 400                                         }
 401                                         if (af == AF_INET) {
 402                                                 /* found ipv4 addr */
 403                                                 hp->h_addrtype = AF_INET;
 404                                                 hp->h_length =
 405                                                     sizeof (struct in_addr);
 406                                                 hp->h_addr_list[ind] =
 407                                                     (char *)&h->h4_addr;
 408                                                 ind++;
 409                                         } else {
 410                                                 /* found v4mapped addr */
 411                                                 hp->h_length =
 412                                                     sizeof (struct in6_addr);
 413                                                 hp->h_addr_list[ind] =
 414                                                     (char *)&h46_addr[ind];
 415                                                 IN6_INADDR_TO_V4MAPPED(
 416                                                     &h->h4_addr,
 417                                                     &h46_addr[ind]);
 418                                                 ind++;
 419                                         }
 420                                 }
 421                         }
 422                 }
 423         }
 424         return (ind > 0 ? hp : NULL);
 425 }